Teenage perpetrators of domestic violence are to be targeted by the government in a hard-hitting awareness campaign that reflects concern about physical abuse meted out by the young.

The move, part of the government's Violence Against Women and Girls strategy, highlights fears that if people under 20 commit domestic violence, it will become the norm for them in later life.

Research by the NSPCC reveals that a third of teenage girls in a relationship suffer an unwanted sexual act. A quarter of girls also suffer physical violence, such as being slapped, punched or beaten by their boyfriend.

The campaign, which will start in the new year, is aimed at both sexes and aims to challenge what the home office claims are "pervasive attitudes among teens".

"Violence against women and girls shatters lives and has a lasting impact across generations," said the home secretary, Alan Johnson. "It is vital that we challenge the troubling and persistent attitudes among some teenagers that violence in relationships is ever justified. Catching them in their first relationships before these views become entrenched should help to prevent violence."

The campaign, which will be supported in schools and carried on television, aims to ensure that girls understand they do not have to tolerate any form of violence or controlling behaviour. It will help young people understand what constitutes abusive behaviour in a relationship by covering a range of messages from physical violence through to being pressured to have sex.

The campaign will be unveiled on Wednesday, International Day for the Elimination of Violence against Women, and will be included alongside a range of measures involving the police, councils, the NHS and government. It comes as new research suggests that three quarters of police forces are insufficiently trained to tackle domestic abuse.

Freedom of information (FOI) requests made to England and Wales's 43 police forces have revealed substantial inconsistencies in how domestic violence victims are treated. Forces were asked about budgets, training, staffing and operational structures. Their responses revealed substantial regional differences.

The FOI requests found at least 10 different ways in which police forces classified a domestic abuse incident. In almost one force in 10, incidents are not logged as domestic abuse unless the offence is a violent crime. Only 25% of forces providing specialist domestic abuse training.

More than four-fifths of the forces questioned work with independent domestic violence advisers and domestic abuse co-ordinators, who are widely recognised as the most valuable members of a domestic abuse unit. But in some cases there was only one of these serving regions with populations of 500,000. Even in the best-staffed force, there was just one adviser or co-ordinator per 45,000 members of the public.

Last week, the Association of Chief Police Officers proposed a domestic violence register to track the estimated 25,000 men in England and Wales who move from one relationship to another, serially abusing their partners.

But Liquidlogic, which builds computer systems for the police, said the FOI results suggested the register should not be the priority. "A complete overhaul is needed if we are to achieve truly effective response and support for domestic abuse victims and their children," said Denise Harrison, one of the firm's directors.